The conventional Universal Serial Bus (USB) on-the-go (OTG) host device, such as data bank, usually has one or two USB ports for connecting to peripheral device which is compatible to USB protocol. The USB OTG host device further includes Integrated Drive Electronics (IDE) port for connecting a hard disk drive so that the data content in the USB peripheral device, e.g. portable disk, connected to the USB port may be copied to the hard disk drive in the IDE port. In addition, memory card reader for reading and writing a variety of memory cards, such as secure digital (SD) memory card, multi-media card (MMC), and memory stick card, only supports the data copy from the card reader to the IDE port in one-way mode. That is, the data content in the flash memory card is reproduced to the hard disk drive in single-directional mode.
Specifically, the USB OTG host devices do not support the reverse data transmission. In other words, the data content in the hard disk drive and the flash memory card connected to the card reader cannot be copied to the USB peripheral device. Conventionally, to accomplish this application, a desktop personal computer (PC) or a notebook computer is utilized to perform the reverse data transmission from the hard disk drive and the flash memory card, respectively, to the USB peripheral device. It is quite inconvenient and time-consuming for the users. Therefore, the conventional USB OTG host devices only support a few types of memory card and one-way data transmission, and thus the availability of USB OTG host devices is limited. This further disadvantageously restricts the usability of the USB peripheral devices.
Consequently, there is a need to improve the USB OTG host device to solve the aforementioned problems.